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arXiv · 0911.3206

Large polaron formation induced by Rashba spin-orbit coupling

C. Grimaldi
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Abstract

Here the electron-phonon Holstein model with Rashba spin-orbit interaction is studied for a two dimensional square lattice in the adiabatic limit. It is demonstrated that a delocalized electron at zero spin-orbit coupling localizes into a large polaron state as soon as the Rashba term is nonzero. This spin-orbit induced polaron state has localization length inversely proportional to the Rashba coupling $γ$, and it dominates a wide region of the $γ$-$λ$ phase diagram, where $λ$ is the electron-phonon interaction.

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C. Grimaldi. 2010-02-09. Large polaron formation induced by Rashba spin-orbit coupling. https://doi.org/10.1103/physrevb.81.075306

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